from textual.app import App, ComposeResult
from textual.widgets import Label
 
class HelloWorld(App):
    """一个简单的Hello World应用"""
 
    def compose(self) -> ComposeResult:
        yield Label("你好，世界!")
 
if __name__ == "__main__":
    app = HelloWorld()
    app.title="起步示范"
    app.run()